Not Applicable
Not Applicable
Many manufactured products or components of products are considered to be fungibles, that is to say each product or component is virtually identical with the other. In reality, such manufactured products or components are made within certain tolerances, so that the differences between those products are within an acceptable range of measurable physical properties. In many applications, the consumer of a manufactured product is unconcerned with the specific physical properties of that product, so long as the product falls within the specified tolerance levels presented by the manufacturer.
However, in certain applications, a consumer of a manufactured or OEM part must make accommodations for even miniscule variations within the manufactured part, regardless of whether or not the product falls within the tolerances presented by the manufacturer. Thus, the consumer needs to know the exact measurements of the part, rather than just the nominal measurements of the part. Heretofore, the consumer would resort to physically measuring the manufactured part to determine its true and exact dimensions. For example, the consumer of anti-friction bearings may require the inner diameter of the inner race surface or bore size to be of an exact dimension to fit on a shaft of a particular size to avoid an excessive pre-load on the bearing. The consumer of such an anti-friction bearing traditionally would measure the bearing with a precision device, such as a laser micrometer to determine the actual inner diameter, and then grind the inner diameter of the bearing or apply shims to the bearing, as necessary, to obtain a proper fit of the bearing on the shaft.
The manufacturer of the anti-friction bearing may make physical measurements of each product, for quality control or other purposes. Therefore, the manufacturer of the anti-friction bearing may have the actual physical properties of each manufactured product produced. However, due to traditional arrangements between suppliers and customers in which a customer purchases a component within a guaranteed tolerance range, the supplier does not make use of any measured component data beyond its own internal quality control practices. Thus, the customer knows only the nominal dimensions of the manufactured part, and that the part is within whatever tolerances are specified for the part.
The typical anti-friction bearing has inner and outer races provided with opposed raceways and rolling elements which are located between the races where they roll along the raceways when the bearing is set in operation, thereby reducing friction to a minimum. The bearing often contains a lubricant and its ends are closed by seals to exclude contaminants from the interior of the bearing and of course to retain the lubricant in that interior. A bearing often fails for lack of lubrication or by reason of a defect in one of its raceways or rolling elements. But when assembled, the raceways and rolling elements are totally obscured and cannot be inspected without disassembling the bearing. This, of course, requires removing the bearing from the object upon which it is installed, such as a rail car journal, a vehicle axle, or a mill roll, for example.
Sometimes, a defect in an anti-friction bearing may manifest itself in a condition that is subject to detection on the exterior of the bearing, although not necessarily through a visual inspection. For instance, a rise in temperature can denote a lack of lubrication, or perhaps, even a seizure in which both races turn and the anti-friction bearing in effect becomes an unlubricated sleeve bearing. Also, spalling or other defects in the raceways or rolling elements may produce excessive vibrations in the bearing.
Devices exist for monitoring the operation of bearings. For example, railroads have trackside infrared sensors which monitor the journal bearings of passing trains, but they exist at a relatively few locations often many miles apart and will not detect the onset of a temperature rise occurring between such locations. Some bearings come equipped with their own sensors which are coupled to monitoring devices through wires. As a consequence, the race which carries the sensor for such a bearing must remain fixed, that is to say, prevented from rotating, or the wires will sever. And with a railroad journal bearing, at least, the outer race preferably should remain free enough to,xe2x80x9ccreepxe2x80x9d, that is rotate in small increments, so that wear is distributed evenly over the circumference of the outer raceway. Furthermore, preventing cup creep requires a costly locking mechanism.
Another problem facing the user of an anti-friction bearing is that of verifying the authenticity of those bearings. The user typically expects the bearing to be produced by the manufacturer listed on the packaging of the bearing. However, it is becoming common for unscrupulous manufacturers to produce counterfeit parts, labeling those parts under a respected, recognized name.
There is therefore a need for a bearing that enables the customer or user of the bearings to quickly and :accurately determine the true and exact dimensions of that individual bearing; for a bearing that enables the user to monitor the performance of the bearing under working conditions; and for a bearing that enables the user of the bearing to verify the authenticity of the bearing.
The present invention relates to devices that provide data about manufactured items and field serviceable products, and more particularly to radio frequency emitting devices that transmit or receive physical measurements, statistical, or inventory data that is embedded in a bearing through such devices. Optionally, the radio frequency emitting devices that transmit data include an appropriate sensor that reflects certain operating conditions of the bearing through the radio frequency emitting device. It is further intended that a bearing fitted with a radio frequency emitting device of the present invention may optionally have unique indicia, such as, for example, a serial or other identification number, for verification of the authenticity of the bearing.
An automatic identification and data capture (AIDC) device for acquiring manufacturing data associated with individual bearings are utilized by a consumer of the bearing, preferably based upon a tag that is attached, either permanently or removably, to the bearing. By encoding physical properties of the bearings in a radio frequency (RF) tag for example, a consumer of the bearings may receive physical data specific to the particular bearing by using a receiver or reader. The data is processed by a microprocessor controlled device, such as for example a computer, PDA, or other devices well known in the art. Thus, the consumer is not required to measure the desired physical characteristic of the bearing, but may make modifications to or accommodations for the bearing based upon the data obtained from the manufacturer through the RF tag.